McNeil, of Mifflin Street near 6th, was also held for trial for attempting to rob Melquidas Moreno Allende, 22, the victim's friend who called 9-1-1 in the aftermath of the shooting.
Carney, 19, while testifying for the prosecution, reluctantly confirmed the statement he gave homicide detectives two days after the slaying.
"Y'all got it on paper. Y'all already know," he repeatedly said when asked by Assistant District Attorney Gwenn Cujdik to repeat what McNeil told him about committing the slaying.
In the statement, which Cujdik read, Carney said McNeil told him and several other friends that he was riding around on a bicycle looking for someone to rob when he saw two Mexicans.
McNeil ordered the victims to give up their money but Aparicio refused to hand over his backpack and tried to flee, so he shot him, Carney said McNeil told him.
McNeil ran off without stealing anything and left his bike at the crime scene, the prosecutor said. That piece of evidence helped detectives find Carney, who rode the bike earlier in the day and left behind fingerprints, she said.
"His testimony corroborates all the other evidence we have, the physical evidence and the evidence from witnesses," Cujdik said of Carney, who was brought to court from a Delaware County jail, where he is being housed for an unrelated drug arrest. "More than that, it's an admission from [McNeil].
"He bragged about it. You have to interpret what he said as him bragging," Cujdik said of McNeil.
Aparicio had just finished his shift as a barback at the Public House bar, 18th Street near Arch, when he and Allende went to visit Aparicio's brother at the bakery where he worked, near the shooting scene.
Samuel Aparicio, who was aided by a Spanish-language interpreter for his testimony, said he stepped outside the bakery then went back inside to turn off an oven when he heard his brother's friend yell.
"When I came out, my brother was already lying on the other side of the sidewalk," Samuel said.
Police Sgt. Jeremy Brosious testified that when he arrived Aparicio was unconscious and was being cradled by the man who had called 9-1-1.
Frantic and sobbing, Brosious said the man said that he and Aparicio were sitting together outside the bakery when a black man dressed in black pants and a black hoodie approached, pointed a gun and demanded money.
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